After developing his skills with the junior club of his hometown, Turku, Finland, Salo turned professional with TPS of the SM-Liiga in 1994–95. He appeared in seven games, recording a goal and two assists in his first season in the SM-Liiga. The following campaign, he recorded a Finnish career-high 14 assists and 21 points over 47 games. In the off-season, Salo was selected by the Ottawa Senators with their last selection in the 1996 NHL Entry Draft, 239th overall in the ninth round. He remained in Finland for two more seasons upon being drafted. He improved from seven goals to nine in 1996–97. The following season, he transferred from TPS to Jokerit. In his lone season with the Helsinki-based team, he tallied three goals and eight points over 35 games.

Following a four-year career in Finland, Salo signed with the Senators in July 1998.[1] He played in the first 3 games of the 1998/99 season before he was assigned to the Detroit Vipers, Ottawa's International Hockey League (IHL) affiliate, due to his first NHL injury and was recalled on 18 November 1998.[2] Twenty-seven games into his rookie campaign, he scored his first NHL goal against Boston Bruins goaltender Byron Dafoe, a game-winner, in a 3-1 win on 21 January 1999.[3] Completing the 1998–99 season with seven goals and 19 points, he was named to the NHL All-Rookie Team.[4] The following season, Salo notched a hat trick in a 6–4 win against the Pittsburgh Penguins on 30 March 1999.[5] His campaign was shortened, however, to 37 games due to injury and he was limited to 14 points. In 2000, he missed two games as he suffered from a snakebite.[6]

Salo continued to be sidelined in 2000–01 with various ailments, including shoulder, foot and knee injuries, as well as the flu.[7] In March 2001, he was also cross-checked in the face by Rick Tocchet of the Philadelphia Flyers, suffering broken teeth and a mild concussion.[8] He finished his third NHL season with 18 points in 31 games.

Before the 2001–02 season began, Salo injured his groin in an exhibition game against the Toronto Maple Leafs in September.[7] In addition to missing the first three games of the season, he was later sidelined for a total of 13 more contests due to separate cases of the flu, a broken finger and back spasms.[4] He recorded 18 points in 66 games. In the proceeding off-season, Salo underwent shoulder surgery.[9] Becoming a free agent, he accepted an $880,000 qualifying offer from the Senators on 31 July 2002.[9] Nearly two months later, he was traded to the Vancouver Canucks in exchange for forward Peter Schaefer on 21 September.[4]

Salo established himself as a top-four defenceman with the Canucks, ranking fourth among team blueliners in average ice time per game during his first season with Vancouver.[10] He also appeared in a career-high 79 games while recording nine goals and 30 points. The Canucks re-signed him in the off-season to a two-year, $3.2 million contract.[11] The following campaign, he recorded seven goals and 26 points in 74 games.

Due to the 2004–05 NHL lockout, Salo went overseas to play for Frölunda HC in the Swedish Elite League. He notched six goals and 14 points in 41 games, helping Frölunda to the league's best regular season record.[12] The club went on to capture the Le Mat Trophy as playoff champions, defeating Färjestads BK four games to one in the finals.[13] Salo assisted on the overtime goal by Niklas Andersson in game five to win the championship.[14] Salo completed the playoffs with a goal and seven points in 14 post-season contests.

As NHL play was set to resume the following season, Salo signed another two-year contract with the Canucks at $1.5 million per season.[15][16] He was limited to 59 games in the subsequent 2005–06 season, suffering a shoulder injury with the Finnish national team during the 2006 Winter Olympics, colliding with a teammate during a line change.[17] He recorded 10 goals and 33 points with the Canucks, second among team defencemen in scoring.[18] His 23 assists were also a career-high.

In 2006–07, Salo sprained his knee in a game against the Minnesota Wild on 2 November 2006.[19] Soon after returning, he sustained nerve damage in his shoulder from a hit against the Edmonton Oilers in December.[20] Towards the end of the season, he suffered a groin injury, sidelining him for five games in March and April.[4] Although he cumulatively missed 15 games, Salo still managed to have a career year, recording personal bests with 14 goals, 23 assists and 37 points. He tied for 10th among league defencemen in goals and ranked first in game-winning goals with six.[21][22] Late in the season, he avoided his pending unrestricted free agency by re-signing with the Canucks to a four-year, $14 million contract extension on 29 March 2007.[23] The Canucks entered the 2007 playoffs as the third seed. After eliminating the Dallas Stars in the first round, Vancouver was defeated by the Anaheim Ducks in five games. Salo missed the first two games of the second round due to the flu.[4] He notched an assist over 10 post-season games.

With an accumulation of injuries over the years, Salo spent the 2007 off-season recovering from chronic groin, back and shoulder problems. Salo was immediately sidelined once more before the start of the 2007–08 season, fracturing his wrist during an intra-squad game in training camp.[24] Shortly after returning, he was hit in the face by a clearing attempt from teammate Alexander Edler during a game against the Nashville Predators on 2 November 2007.[25] The impact from the puck broke his nose and he missed 19 games.[25] In 63 games, Salo recorded 25 points, his lowest output since his 2001–02 season with the Senators. Despite this, he still led all Canucks defencemen in scoring, as all the team's blueliners also suffered injuries over the season.[26]

Salo practicing with the Canucks in 2012

The 2008–09 season began with more time off in November due to separate leg and shoulder injuries.[27][28] After returning, he was hit into the boards by Edmonton Oilers captain Ethan Moreau on 17 December 2008, and suffered a broken rib.[29] He missed 15 games before returning on 20 January 2009.[4] Limited to 60 games, he managed five goals and 25 points in the regular season. In the ensuing playoffs, Salo scored seven points in seven games, including game-winning goals in both game ones of the first and second rounds against the St. Louis Blues and Chicago Blackhawks, respectively.[30][31] Salo injured himself in game two of the second round, tearing his gluteus medius muscle while taking a slapshot in which he scored. He played through the injury the following game before missing the next two matches.[32] Following his return, the Canucks were eliminated in the sixth game by the Blackhawks. Salo had three goals and seven points in seven games.

Early in the 2009–10 season, Salo suffered a medial collateral ligament (MCL) sprain to his right knee during a game against the Dallas Stars on 11 October 2009.[33] Sidelined for seven games, he returned by the end of the month.[4] Salo missed additional games during the season to various injuries,[4] ending the campaign with nine goals and 28 points in 68 games. Towards the second half of the season, Salo took on a more defensive role, replacing Willie Mitchell, who was sidelined with a concussion, as the team's primary shutdown defenceman.[34]

In game five of the second round of the 2010 playoffs, Salo was hit in the groin by a slapshot from Chicago Blackhawks defenceman Duncan Keith. Needing to be helped off the ice, he was taken to hospital with what was falsely believed to be a ruptured testicle.[35][36] He played through an undisclosed injury the following game, as the Canucks were eliminated by the Blackhawks by a 5–1 score.[37] He completed the playoffs with a goal and six points in 12 post-season games.

Playing floorball in the off-season, Salo tore his achilles tendon on 22 July 2010.[38] After undergoing surgery, he was sidelined for the first four months of the 2010–11 season. The injury was so severe that Salo later admitted thinking his career was over during his rehabilitation.[39] Before returning to the Canucks lineup, he was sent to the team's American Hockey League (AHL) affiliate, the Manitoba Moose, for a conditioning assignment. Making his AHL debut on 4 February 2011, he scored two goals for the Moose in a 3–2 win against the Wilkes-Barre/Scranton Penguins.[40] Salo played two more games for the Moose, going pointless in both, before being called up by the Canucks on 11 February.[41] Salo appeared in 27 games in 2010–11, recording three goals and four assists. During the first and second rounds of the 2011 playoffs, Salo missed four games with a leg injury.[4] The Canucks eliminated the Blackhawks and Nashville Predators in the first two rounds to qualify for the Western Conference Finals against the San Jose Sharks. During Game 4 of the series, Salo set a Canucks playoff record for fastest back-to-back goals, scoring 16 seconds apart on a pair of 5-on-3 powerplays. The feat also tied Larry Murphy's NHL record for fastest two power play goals in the playoffs since 1957.[notes 1][42] Combined with Ryan Kesler's goal a minute and thirty-nine seconds previously, the trio of goals were also the fastest scored in Canucks playoff history at a minute and fifty-five seconds. Vancouver went on to win the game 4–2,[43] while winning the series 4–1. Advancing to the 2011 Stanley Cup Finals, the Canucks were defeated in seven games by the Boston Bruins. During the off-season, Salo re-signed with the Canucks to a one-year, $2 million deal on 1 July 2011, prior to becoming an unrestricted free agent.[44]

Salo with the Lightning in 2013.

In the first half of the 2011–12 season, Salo suffered a minor groin injury that sidelined him on two separate occasions, costing him three games and one game, respectively.[4] In January 2012, the Canucks and Bruins played against each other for the first time since the 2011 Stanley Cup Finals. During the contest, Salo sustained a concussion after a clipping hit from opposing forward Brad Marchand. Salo left the game immediately, while Marchand received a five-minute major and game misconduct; he was later additionally suspended for five games following a hearing with the league.[45]

On 13 December 2001, Salo was selected to the Finnish national team for the 2002 Winter Olympics in Salt Lake City, along with Senators teammate Jani Hurme.[50] He appeared in four games without registering a point as Finland was defeated by the gold-medal winning Canadians in the quarterfinal by a 2–1 score.[51]

In Salo's next World Championships appearance in 2004, he recorded three assists in seven games. Finland failed to medal, losing their quarterfinal to Canada.[52] Salo assisted on the go-ahead goal in the third period before Canada tied up the score and won 5–4 in overtime.[52] Several months later, at the 2004 World Cup, Salo helped Finland to the final, notching three assists in seven games. For his third straight national team appearance, however, Finland was eliminated by Canada, losing the championship game 3–2.[53]

He made his second Olympics appearance at the 2006 Games in Turin. He recorded four points in six games before suffering a tournament-ending shoulder injury in a collision with teammate Ville Peltonen during a line change in front of the team bench.[17] The injury kept him from playing in the semifinal and gold medal game, where Finland won the silver medal in a 3–2 loss to Sweden.[54] Despite missing two games, Salo ranked second among team defencemen, behind Kimmo Timonen, with a goal and four points in six games.[55] Four years later, Salo competed once again for Finland at the 2010 Winter Olympics in his NHL hometown Vancouver. He recorded two points in six games, while leading all Finnish players in ice time.[56] He scored his lone goal during the bronze medal game, opening the score against Slovakia in a 5–3 win.[57]

Salo is known as a two-way defenceman, capable of being matched up against opposing team's top players,[34] while also contributing offensively. His offensive game is characterized by his powerful slapshot.[58] He has won numerous hardest shot titles with the Canucks in the team's SuperSkills competitions,[58] clocking one shot at 102.7 miles-per-hour (163.5 kph) in 2012.[59] As a result, he is used frequently on the powerplay, being set up by teammates for shots from the point.[58] A well-rounded defenceman, Salo also earns time on the penalty kill.[60]

Salo has a wife, Johanna, and three children. From youngest to oldest, they are Peppi, Oliver and Julia.[61] Salo has spent time coaching Oliver, his only son, on his hockey team.[62]

Growing up in Turku, Finland, Salo had aspirations of playing with the Finnish national team, rather than the NHL.[62] He idolized Jari Kurri and was more familiar with other Finnish players, such as Esa Peltonen and Heikki Riihiranta, than he was with any NHL stars.[62]